Project Description

SEL-411L Advanced Line Differential Protection, Automation, and Control System

Apply the SEL-411L Relay for complete protection and control of any transmission line. The SEL-411L provides differential protection with both phase- and sequence-based operating elements for sensitivity and high-speed operation. Choose from many popular fiber and multiplexed communications options. Distance protection and logic from a complete SEL-421 Protection, Automation, and Control System are included to provide backup protection and integration. Any transmission line (short, long, or series-compensated) can be well protected with the SEL-411L Relay.

Functional Overview

21

Phase and Ground Distance

25

Synchronism Check

27

Undervoltage

32

Directional Power

50

Overcurrent

50BF

Dual Breaker Failure Overcurrent

51

Time-Overcurrent

59

Overvoltage

67

Directional Overcurrent

68

Out-of-Step Block/Trip

79

Single-/Three-Pole Reclosing

81

(O, U) Over-/Underfrequency

85

RIO SEL MIRRORED BITS Communications

87

Current Differential

DFR

Event Reports

ENV

SEL-2600

HMI

Operator Interface

LGC

Expanded SELOGIC Control Equations

MET

High-Accuracy Metering

PMU

Synchrophasors

SER

Sequential Events Recorder

BRM

Breaker Wear Monitor

LDE

Load Encroachment

LOC

Fault Locator

SBM

Station Battery Monitor

Front- and Rear-Panel Diagrams

Front

Rear

Line Current Differential, Distance, and Directional Overcurrent Protection

Apply single- or three-pole subcycle current differential protection for up to four terminal lines, even with two breakers per terminal.

Implement subcycle operation and superior security with five zones of phase and ground distance elements as well as directional overcurrent elements.

Reduce protection system costs by stocking one relay for line protection using a combination of the differential, distance, and overcurrent elements to meet your application needs.